Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Accumulated Amortization	$ 14.9	$ 5.3
Net Carrying Amount	14.8
Indefinite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	37.8	37.8
Intangible assets	22.9	32.5
Insurance licenses
Indefinite-Lived Intangible Assets [Line Items]
Intangible assets	7.5	7.5
Trademark
Indefinite-Lived Intangible Assets [Line Items]
Intangible assets	$ 0.6	0.6
Technology
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	3 years
Gross Carrying Amount	$ 28.0	28.0
Accumulated Amortization	13.2	3.9
Net Carrying Amount	$ 14.8	24.1
VOBA
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	6 months
Gross Carrying Amount	$ 1.7	1.7
Accumulated Amortization	1.7	1.4
Net Carrying Amount	$ 0.0	$ 0.3